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Mention e-cigarettes in a room with health experts, tobacco company representatives, and officials from the Food and Drug Administration (FDA), and you’ll probably start a verbal war about their benefits, harms, and regulations, among the more impersonal things. Something that’s likely to come up on the “harms” side is information from a new study, which found that 10 new e-cigarette brands and 240 new flavors emerged on the internet each month over the course of six months.

There’s no doubt that e-cigarettes have some appeal for smokers who wish to quit smoking. Although it’s unclear how many chemicals an e-cigarette user is inhaling, chances are there are far less than regular cigarettes, which can have as many as 7,000. In fact, a recent study found that smokers were 60 percent more likely to quit if they used the devices. But with so many brands and flavors emerging, the breadth of the industry may become more of a threat to the public health, especially for younger people, than a useful tool for smokers.

The researchers scoured English-language websites that marketed e-cigarettes over the course of two time periods: May 2012 to August 2012 and December 2013 to January 2014. They counted older and newer brands — presumably because of new flavors or features — as well as models, eGos (larger e-cigs with a removable tank), mods (customizable e-cigs), flavors, nicotine strengths, ingredients, and product claims.

During the first time period, they found 288 cigarette brands, however, 37 of them had disappeared when they searched again. During the second time period, another 215 brands appeared. Overall, there were 466 new brands by the end of the study. More astoundingly, there were 7,764 new and unique flavors, including tobacco and menthol. “The number of e-cigarette brands sold on the internet is large, and the variety of flavors staggering,” the researchers wrote in the study, published in the journal Tobacco Control.

The researchers noted, however, that “e-cigarettes were originally invented to mimic conventional cigarette smoking as closely as possible. … Over time, however, the product design has evolved and the advertising messages have changed.” While older brands were still more likely to market their similarities to cigarettes, newer brands touted their versatility and the availability of choices they offered.

A May report from anti-tobacco organization Legacy for Health found that many e-cigarette ads broadcast in 2013 reached teens and younger adults — 58 percent were 12 to 17 years old. But more importantly, they used their ad time to highlight their varieties of flavors, such as Cherry Crush and Peachy Keen. The implications for future teen smoking, or at least vaping, was concerning for the researchers of the current study, which was conducted as part of the State and Community Tobacco Control Research Initiative funded by the National Cancer Institute and National Institutes of Health.

Because it’s unclear how smoking e-cigarettes would affect prevalence of cigarette smoking, the researchers suggested two phases for regulation: First, companies should be “required to properly list ingredients and nicotine strengths,” among other things that ensure safety. Then, e-cigarette companies should ban sales to minors — they may soon be banned from physical sales, but online sales may be harder to regulate — and ban e-cigarette use in indoor areas where cigarette use is banned (already a law in New York City and other cities around the country). With these steps, the FDA can at least reduce the chances that kids will eventually take up cigarettes, the researchers said.